DESC:TECHNICAL FIELD
The present disclosure relates to an offset deformable barrier (ODB) used for crash test of a vehicle. More particularly embodiments relate to an improved offset deformable barrier.

BACKGROUND OF THE DISCLOSURE

A crash test is a form of destructive testing usually performed in order to ensure safe design standards in crash worthiness and crash compatibility for various modes of transportation or related systems and components.
Frontal-impact tests are usually impacts upon a solid concrete wall at a specified speed, but can also be vehicle-vehicle tests.
Offset tests in which only part of the front of the car impacts with a barrier. These are important, as impact forces remain the same as with a frontal impact test, but a smaller fraction of the car is required to absorb all of the force. These tests are often realized by cars turning into oncoming traffic.

The offset deformable barrier (ODB) is used for frontal offset impact tests, and the accuracy of offset deformable barrier (ODB) Finite element (FE) model is very important in achieving a better CAE (Computer aided engineering) correlation in full vehicle crash test.

Currently commercially available FE ODB barriers are ARUP 2000 release, ARUP 2009 release and LSTC ODB model.

The crash performance of the cars are carried out and compared with the crash performance of vehicles with the FE models. The FE models commercially used give out various results in different test parameters and are accurate. The crash performance can be carried out depending on various test conditions and results can be obtained based on varying conditions like Pressure (MPa) vs Deflection (mm), and Deceleration (g) vs Time (ms) etc.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:

Figure 1 – Shows graph of ODB honeycomb material strength requirement as per ECE R94. Test graph is between Pressure (MPa) vs Deflection (mm) showing various Zones.

Figure 2 – Shows Performance graphs of 3 ODB FE models (ARUP 200, ARUP 2009 and LSTC).

Figure 3 – Shows Firewall intrusion plot in comparison with various ODB FE models.

Figure 4 – Shows crash pulse of ODB 64 model in comparison with the ARUP 2000, ARUP 2009 and LSTC models.

Figure 5 – Shows Force vs Deformation comparison of ARUP 2000, ARUP 2009 and LSTC models.

Figure 6 – Shows crash test of a fixed full overlap ODB test set-up with a moving rigid barrier and comparison of test vs CAE results.

Figure 7 – Shows crash test of a fixed partial overlap ODB test set-up with a moving rigid barrier and comparison of test vs CAE results.

Figure 8 – Shows Deceleration comparison between test and CAE in the full overlap ODB test.

Figure 9 – Shows peak deformation of ODB in full width test.

Figure 10 – Shows Deceleration comparison between test CAE in the partial overlap ODB test.

Figure 11 – Shows peak deformation of ODB in partial overlap test.

Figure 12 – Shows Force vs Deformation comparison between test and ARUP 2009 barrier in partial overlap test.

Figure 13 – Shows level of correlation between tests and ARUP 2009 ODB FE model.

Figure 14 – Shows Zones dimensions shown in mm for ARUP 2009 and TML ODB FE model.

Figure 15 – Shows graph of yield stress as a function of the angle off the material axis of various zones.

Figure 16 – Shows flow chart of improved ODB FE model.

Figure 17 – Shows graph of Deceleration pulse for full overlap test.

Figure 18 – Shows graph of Deceleration pulse for partial overlap test.

Figure 19 – Shows resultants of level of Correlation between tests and improved ODB FE model.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION OF DISCLOSURE

The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristic of the disclosure, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and make part of this disclosure.

Referring now to the drawings wherein the drawings are for the purpose of illustrating an exemplary embodiment of the disclosure only, and not for the purpose of limiting the same.

Figure 1 is an exemplary embodiment of the disclosure and illustrates graph of ODB honeycomb material strength requirement as per ECE R94. Test graph is between Pressure (MPa) vs Deflection (mm) showing various Zones. The graph has a standard tolerance band. The honeycomb model structure used in the ODB has to meet the static crush strength requirement. The graph is plotted against Pressure (MPa) and Deflection (mm). The curve in the graph is plotted across various zones as shown in graph. Zone 1, Zone 2 and Zone 3.

Figure 2 is an exemplary embodiment of the disclosure and illustrates performance graphs of 3 ODB FE models (ARUP 200, ARUP 2009 and LSTC). The above mentioned 3 models are tested to a standard ECE R94 requirement model, wherein the graphs are plotted to attain results within the tolerance band as shown in the graph. The results of the 3 ODB FE models (ARUP 200, ARUP 2009 and LSTC) were tested and compared to the ECE R94 standard model.

Figure 3 is an exemplary embodiment of the disclosure and shows Firewall intrusion plot in comparison with various ODB FE models. The peak deformation zone of firewall is shown in red colour and changes with barrier model. The peak deceleration level, time of peak deceleration and the overall shape of the deceleration pulse changes with the barrier model. This firewall intrusion plot shows that ODB FE model plays a critical role in the crash performance of the vehicle in ODB 64 test.

Figure 4 is an exemplary embodiment of the disclosure and shows crash pulse of ODB 64 model in comparison with the ARUP 2000, ARUP 2009 and LSTC models. The crash pulse of the various ODB models is compared by plotting a graph and correlating the graphs obtained by the 3 different ODB models. The graph is plotted for Deceleration (g) vs Time (ms) by having a target peak deceleration as standard on the graph plot.

Figure 5 is an exemplary embodiment of the disclosure and shows Force vs Deformation comparison of ARUP 2000, ARUP 2009 and LSTC models. Stiffness comparison of ODB FE model to compare the stiffness of these ODB FE models were carried out, also static full width compression simulations were carried out. The graph shows the force vs deformation curve of the compression test for the above said 3 barriers. Based on a) the full vehicle ODB 64 simulation results and b) barrier force vs. deformation comparison it is clear that the crash behavior of the 3 FE models is not the same. Physical test was necessary as a reference for comparison so that one barrier model which closely represents the physical ODB model can be selected for the vehicle development program.

Figure 6 and 7 are exemplary embodiments of the disclosure and showing crash test of a fixed full overlap ODB test set-up with a moving rigid barrier and comparison of test vs CAE results and crash test of a fixed partial overlap ODB test set-up with a moving rigid barrier and comparison of test vs CAE results. Two tests were carried out on 2 ODBs with a rigid impactor.
a) In the first test there was full overlap between the ODB and the impactor.
b) In the second test overlap between the ODB and impactor was 60 % of ODB width (600 mm).

Figure 8 is an exemplary embodiment of the disclosure and shows deceleration comparison between test and CAE in the full overlap ODB test. The CAE simulations were also carried out as per the above test set ups for the 3 FE model of ODB. The deceleration levels are measured at the impactor and the relevant time was used for comparison. The plotted graph shows the comparison of test and CAE results for the full overlap ODB test.

Figure 9 is an exemplary embodiment of the disclosure and shows peak deformation of ODB in full width test. The peak deformation of the other three FE ODB tests are compared with the physical test and shows variations in the ODB in deflection (mm). It was observed from the figure 8 and figure 9 that the crash performance of Arup 2009 ODB FE model matches relatively better with test results as compared to Arup2000 and LSTC 2010 ODB FE models. Hence only Arup 2009 model was used for the next assessments.

Figure 10 and 11 are exemplary embodiments of the disclosure and showing Deceleration comparison between test CAE in the partial overlap ODB test and peak deformation of ODB in partial overlap test. In the figure 10 the graph shows ARUP 2009 in comparison with the Physical test results, which shows very similar correlation. Figure 11 shows displacement of the ODB in comparison with the physical test. Physical test peak displacement is 391.2 mm at a time interval of 62.9 ms. whereas the peak displacement of ARUP 2009 barrier is 420.5mm at a time interval of 65 ms.

Figure 12 is an exemplary embodiment of the disclosure and shows Force vs Deformation comparison between physical test and ARUP 2009 barrier in partial overlap test. A graph is plotted between force and displacement of the ARUP 2009 model and the physical test model. The ARUP 2009 has the closest correlation when compared to the physical test model.

Figure 13 is an exemplary embodiment of the disclosure and shows level of correlation between tests and ARUP 2009 ODB FE model. Based on the comparison of the 2 tests and CAE results, it was observed that none of the barriers shows good correlation with the test results. Out of the 3 ODB FE models studied, Arup2009 shows relatively better correlation with the test results. Based on this analysis the level of correlation observed between the tests and Arup 2009 ODB are shown in Figure 13.

Figure 14 is an exemplary embodiment of the disclosure and shows Zone dimensions shown in mm for ARUP 2009 and TML ODB FE model. The correlation data shows a low level correlation between the test and CAE for the Arup2009 ODB barrier. Therefore in order to improve the CAE accuracy on a full vehicle ODB test, the FE model of Arup 2009 ODB has to be improved further.

From the test and CAE comparison it was observed that the overall stiffness of Arup 2009 ODB FE model is lower as compared to the test. The stiffness of Arup 2009 ODB FE model is also low at the time of peak deformation; this is due to the air effect. The ODB model was divided into various zones. The stiffness of each of these zones was calculated based on the stiffness differences between the test and CAE data and accordingly the material model of ODB is modified to achieve the required stiffness. The ODB FE model with above modifications is termed as improved ODB FE model. The schematic of barrier zones in Arup 2009 and improved ODB FE model is shown in Figure 14. The different zone deformations are shown having variations in each zone as shown in the figure. This is done to obtain correlation between the physical test and the improved ODB test.

Figure 15 is an exemplary embodiment and shows graph of yield stress as a function of the angle off the material axis of various zones. The graphs are plotted between Yield Stress (GPA) vs Angle of Material axis (Degree).

Figure 16 is an exemplary embodiment and shows flow chart of improved ODB FE model.

Figure 17 and 18 are exemplary embodiments of the disclosure and showing graph of Deceleration pulse for full overlap test and graph of Deceleration pulse for partial overlap test. Full overlap and partial overlap simulations, as shown in figure 6 and figure 7 were carried out with the improved ODB FE model. The graphs are from the test results obtained from TML ODB FE model.

Figure 19 is an exemplary embodiment of the disclosure and resultants of level of Correlation between tests and improved ODB FE model. The improved ODB FE model is subjected to full and partial overlap tests and a correlation is obtained between the improved ODB FE model and the physical test. Thus we will have an ODB which is more accurate to the proposed standard ODB model. The ODB is improved by providing different stiffness in different zones to bring in a correlation between the physical ODB results and the improved ODB FE model results. The improved ODB has a significant impact on full vehicle ODB crash performance.

EQUIVALENTS

With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

,CLAIMS:1. Offset deformable barrier used for crash test of a vehicle wherein, said offset deformable barrier is used to compare results obtained with various other ODB Fe models are compared with the physical tests which has no correlation, such that improved ODB FE model compares test results of the physical test and ODB FE model and establishes a correlation between the two which helps identifying the key stress strain areas and to improve on the same.